Output device for proof and planograph using electrophotographic recording medium and printing medium thereby

Abstract

An output apparatus for printing a proof sheet and making a planographic printing plate, comprising a printing image data generating means for producing the digital data of a plurality of different color images corresponding to a predetermined number of colors obtained by the color separation of the image data of an original to be printed; a proof sheet outputting means for sequentially forming a screened dot image of each color by using each color toner based on the printing image data derived from said printing image generating means; a planographic printing plate output means for forming a screened dot image of each color by using one recording medium for each color and the oil affinitive toner of each color based on the digital data of each color generated by said printing image data generating means. By providing further a means for compensating for the difference in characteristics between the printing of a proof sheet and the planographic printing (actual printing), one output apparatus can output both the data for printing a proof sheet and the data of the actual printing (the planographic printing).

What is claimed is: 
     
       1. An output apparatus for printing a proof sheet and making a planographic printing plate comprising: generating means for generating printing image data using digital image data of each color corresponding to separated image data of each of a predetermined number of colors obtained by the color separation of an image data to be printed;   an electrophotographic recording medium having a white surface, which comprises a lamination of an electrode and a photoconductive layer and over which a toner image can be formed by a light beam modulated depending on the printing image data;   a proof sheet printing means for forming a screened dot image of each color sequentially by using the toner of each color based on the printing image data over the white surface of said electrophotographic recording medium; and   a planographic printing plate outputting means for forming a screened dot image of each color of oil affinitive toner over the surface of each said electrophotographic recording medium based on said printing image data of each color selected from said printing image data.   
     
     
       2. An apparatus as defined in claim 1, wherein said electrophotographic recording medium contains titanium oxide. 
     
     
       3. An apparatus as defined in claim 1, wherein said toner is a liquid toner. 
     
     
       4. An apparatus as defined in claim 1, wherein the image output apparatus is capable of outputting an image to be printed in both a proof sheet printing mode and a planographic printing plate making mode, and further comprising, in the case of the image output for a proof sheet printing or a planographic printing plate making, a gradation reproducibility correction table, communicating with the generating means and corresponding with said proof printing mode or said planographic making mode for correcting the printing image date. 
     
     
       5. An output apparatus as defined in claim 1, wherein the image output apparatus is capable of outputting an image to be printed in both a proof sheet printing mode and a planographic printing plate making mode, and further comprising two reproducibility correction tables communicating with the generating means for correcting the printing image data in the case of outputting a proof sheet or a planographic printing plate, when one of a proof sheet and a planographic printing plate is outputted, only one gradation reproducibility correction table is used and when the other is outputted, the other gradation reproducibility correction table is used. 
     
     
       6. A printing method for printing a proof sheet, comprising: a step of sequentially forming a toner image of each color by a light beam modulated depending on printing image data of each color based on digital image data of each color corresponding with predetermined separated color data obtained by the color separation of an image data to be printed, over the surface of an electrophotographic recording medium which includes a lamination of a white photoconductive layer on an electrically conductive base and an overcoat layer which is laminated over the surface of said white photoconductive layer in such a way that said overcoat layer can be separated from said white photoconductive layer;   a first proof sheet printing step of applying heat and pressure over the toner images formed over the overcoat layer of said electrophotographic recording medium, thereby causing said toner images to be embedded into said overcoat layer, whereby said electrophotographic recording medium itself is used as a proof sheet; and   a second proof sheet printing step of pressing the surface over which are formed said toner images of said overcoat layer of said electrophotographic recording medium and the surface of a transfer sheet into intimate contact with each other and heating thereby transferring the overcoat layer over which are formed said toner images to said transfer sheet, whereby said transfer sheet integral with said overcoat layer over which are formed said toner images is used as a proof sheet.